Technical Field
The present invention generally relates to a production of puffed food products. The present invention particularly relates to a production of puffed products with irregular shapes. The present invention more particularly relates to a method for a production of popcorn from corn meal.
Description of the Related Art
Corn (Zea mays) is grown worldwide for its use as staple food and industrial applications. The maize plant is often 2.5 meter in height. The stem is commonly composed of 20 internodes (approximately) of 18 cm in length. The leaves grow from each node, and are of generally 9 cm in width and 120 cm in length. The elongated stigmas called silk emerge from the whorl of husk leaves at the end of the ear. The elongated stigmas have a pale yellow color and a length of 18 cm. The elongated stigmas appear like tufts of hair and at the end have a carpel. The carpel may develop into a “kernel” if fertilized by a pollen grain. The pericarp of the fruit is fused with the seed coat referred to as “caryopsis” that is typical of the grasses and the entire kernel is often referred to as “seed”. The cob is close to a multiple fruit in structure, except that the individual fruits (kernels) never fuse into a single mass. The grains/kernels are of the size of peas and adhered in regular rows around a white pithy structure which forms the ear. The maximum size of maize kernel is reported to be 2.5 cm. An ear commonly holds 600 maize kernels. The maize kernels are of various colors, such as blackish, bluish gray, purple, red, white and yellow. When the maize kernels are grinded into flour, the flour yield is more with much less bran when compared to wheat flour. The maize kernel flour lacks the protein gluten of wheat and therefore makes baked goods with poor rising capability. The genetic variant that accumulates more sugar and less starch in the ear is consumed as a vegetable and is called sweet corn. Young ears can be consumed raw, with the cob and silk, but as the plant matures (usually during the summer months) the cob becomes tougher and the silk dries to inedibility. By the end of the growing season, the maize kernels dry out and become difficult to chew without cooking them tender first in boiling water.
The leafy stalk produces ears which contain the grain, the grains are seeds called kernels. Maize kernels are often used in cooking as a source of starch (carbohydrate). The major cultivated corn types are flour corn (Zea mays var. anylacea), popcorn (Zea mays var. everta), Dent corn (Zea mays var. indentata), Flint corn (Zea mays var. indurata), Sweet corn (Zea mays var. saccharata), Waxy corn (Zea mays var. ceratina), Amylo-maize (Zea mays), Pool corn (Zea mays var. Tunicata Larranga) and Striped maize (Zea mays var. Japonica).
The corn (Zea mays) is used as human food (in the form of tacos, tortillas, polenta, bread, snack food, corn flakes), corn starch, cooking oil (corn oil), fructose corn syrup, sweetener, maize grain alcohol and for feeding livestock.
The oldest and the most popular puffed snack product is popcorn which is prepared by heating kernels of popping corn until they explode. The cost and nutritional value of natural corn used for making popcorn are directly determined by the price and quantity of the popping corn. The quality of the corn used also determines the size and textures of the expanded corn pieces and the percentages of the kernels which are successfully converted into expanded product pieces (popcorns). It is therefore difficult to produce a natural popcorn of uniformly high quality and there is no opportunity to reduce its cost. The nutritional value of natural popcorn is not readily altered except by additives (flavoring agent, fats, salt etc) which increase cost.
Snacks and cured products have been commonly puffed or expanded in the past by any of one of the methods including extrusion, fat frying, salt puffing and hot air puffing. In the well known methods for extruding a snack or ready to eat cereal, flour, such as wheat flour or rice flour is mixed with water to form a dough which is subjected to a screw type extruder. The screw mechanism applies a substantial amount of force to the dough, and increases the temperature of the dough to a point at or above 212° F. The dough is then extruded, water is flashed off and the flour based product is expanded. Another conventional method for preparing a puffed snack includes mixing flour material of corn, wheat, oats, barley, rye or other cereal with water and cooking the dough in a steam jacketed cooker. The cooked dough is extruded under low pressure so that there is little or no puffing during extrusion. The extrudate is cut into pieces and then expanded in a process such as by deep fat frying.
The conventional method of producing popcorn leads to the yield of popcorn which are gritty and lead to tooth-packing. It is also recognized that the quality of popcorn is subject to considerable variation. Thus some types of popcorn produce relatively small kernels of popcorn, while others produce much larger kernels. Moreover the number of kernels of popcorn also varies quite substantially for the reason that different grades of popcorn pop to a greater or less extent. With some types of popcorn, the number of unpopped kernels constitutes a substantial proportion of the corn supplied to the popping apparatus. Some control over the popping qualities of popcorn can be obtained by adjusting their moisture content and the like, but nevertheless it is difficult to obtain a product of uniformly high quality even in large commercial operations.
Prior arts disclose a process of producing a simulated popcorn product of uniform high quality from cornmeal. In the process, white or yellow cornmeal (or a mixture) with a moisture content of 10 and 12.3% is forced at a high velocity of 950-1800 inches per minute, by means of high pressure through extrusion orifices. The cornmeal is discharged from the orifices in rods which resemble branches with numerous irregularly shaped buds extending from their sides in generally equally spaced clusters. By cutting these rods into small pieces as the rods are extruded, simulated popcorn pieces are formed.
While the prior art process provides a means of producing corn product pieces which are more uniform in size and quality, it does not provide a way to materially improve the nutritional value of the product. With the natural popcorn, the protein, vitamin and mineral content of the final product is that of the raw corn used. Also the potential cost reduction is limited by the fact that cornmeal having a moisture content within the narrow range of 10 to 12.3% must be selected for use in the process. This critical moisture range limits the sources of supply to those of known moisture content (which would tend to be higher in price) or requires that the purchased cornmeal be tested to determine the moisture content. While cornmeal having a lesser moisture content is also used with the addition of water, it is necessary to determine the moisture content of each batch of cornmeal before use, thus increasing costs.
There are drawbacks with the conventional methods of popping corn. To pop “popcorn” the kernels must be heated so that internal heat buildup cause the kernel to explode. Once the kernel has exploded, it is desirable for the cooking process to stop.
One conventional method of popping corn is to heat the kernel on a hot surface. There are drawbacks in this method. First, the heating surface affects a small volume of the kernels. The spot on the kernel that contacts the hot surface. Second the “husk” (outer surface) of the kernel tends to burn on the spot that contacts the hot surface. Once the kernel has popped, the popped kernel including the attached husk, continues to burn on the spot that contacts the hot surface because the popped kernels are not separated from the un-popped kernels. The burnt spots give the popcorn an undesirable burn taste.
To help alleviate this problem, one may share or constantly stir the popped and un-popped kernels. Additionally, the heated surface temperature may be reduced. Finally, the cooking process can be stopped before all the kernels are popped. The result is that there still is a burn taste. The process is slow and not all the kernels are popped leaving waste kernels mixed in with the popped kernels.
Another conventional method to cook the kernels is to use hot oil. This tends to speed up the heat transfer to the kernel and provide a more uniform application of heat to the kernel. While this process addresses spot burning, cooking with oil has its disadvantages. Hot oil can still burn the popcorn if the oil is too hot or if the kernel takes too long to pop. Further it leaves an undesirable residue on the popcorn that carries the burn taste from burnt kernels to the popped corn. Finally the popped kernels continue to cook after popping.
A third method of popping corn is by the use of an oven. Conventional ovens, however cannot transfer heat to the inside of the kernel fast enough to be speed efficient. And the problems of over cooking the popped corn and the presence of wasted un-popped kernels are still present.
Microwave popping corn addresses the most pre-dominant problem of popping corn speed. But still the problems of spot burning, over cooking of the husk and popped corn and left over un-popped kernels are still present. Additionally microwave popping of corn is hard to do in mass quantities.
Hot air popping machines which cook the kernels with swirling hot air, addresses the spot burning problem. The popped corn however still swirls in hot air after popping so over cooking is still a problem. Further the speed is never sufficient.
Hence, there is a need for a method/process for producing popcorn without any spot burning of popcorn, preventing a continuation of cooking even after a completion of popping of corn, without any residue on the popped corn and preventing any leftover of un-popped maize kernels. Also there is a need for a method for producing popcorn from cornmeal instead of maize/corn kernel.
The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.